The State Department yesterday appeared to be pulling back from President Reagan's offer of a possible meeting here with a Jordanian-Palestinian delegation as Secretary of State George P. Shultz said that "the action is in the Middle East" in terms of reviving the Arab-Israeli peace process.

But at the same time, Shultz said he is eager "to keep the ball rolling" in light of new Arab proposals to revive the Middle East peace process.

Shultz held an unscheduled second meeting yesterday with Jordanian Foreign Minister Taher Masri after Reagan's statement at his Thursday news conference that "we're willing to meet with a joint group." His offer sparked speculation about increasing U.S. interest in Arab proposals and possible imminent shifts in the previously cautious U.S. attitude toward them.

But after the meeting with Masri, Shultz told reporters: "The possibility of visits here is one thing. But the parties are really in the Middle East. So I think likely that's where the action most likely will be."

Even before Shultz spoke, administration officials insisted that Reagan's offer did not signal a change in the longstanding U.S. policy of trying to bring about direct talks between Israel and its Arab neighbors.

They said that Reagan had meant to indicate his willingness to meet such a delegation if the move showed promise of leading to direct talks. But, the officials added, this idea was only one of the options being considered by the administration, and they added that the United States had not yet decided what course offers the best chance for movement toward negotiations. The issue is delicate for all parties because of the implication that U.S. reception of a joint Arab delegation would be tantamount to recognition of the Palestine Liberation Organization.

Reagan tried to circumvent that problem by reiterating U.S. refusal to accept any PLO members in the delegation prior to PLO recognition of Israel's right to exist.

Israeli Prime Minister Shimon Peres, while expessing willingness to negotiate directly with a Jordanian-Palestinian delegation that has no PLO members, publicly has opposed the idea of such a group going to Washington for prelimi- nary talks that would not include Israel.

White House spokesman Larry Speakes said Israel has sent "some mixed signals" about its attitude on U.S. talks with a Jordanian-Palestinian delegation. "There are some indications that they [Israel] would be interested," Speakes said.

But yesterday the Israeli Embassy here reiterated Israel's concern that the Arabs would use a Washington meeting to circumvent direct talks with the Jewish state and to bring members of the PLO into the process "through the back door."

Reagan's additional comment Thursday that "we are not getting into the direct negotiations" created confusion about whether the United States was on the verge of renewed activism in the peace process or was distancing itself from increased involvement.

A senior U.S. official, commenting on Reagan's statement, said he was trying to underscore the U.S. belief that the Arabs and Israelis must resolve their differences between themselves. But, the official added, Reagan did not mean to imply the United States was withdrawing from its role as "a full partner" in the American-sponsored Camp David accords.

He said the United States would continue to act as a mediator if the peace process could be revived and expanded with Jordanian participation.

At a meeting with reporters earlier yesterday, Masri said he did not know what the mechanism for selecting the Palestinian members of the delegation might be, and he proposed that the United States should suggest names Jordan could pass on to the PLO for its consideration.

"We didn't try to work out anything of that kind," Shultz said after the 40-minute session with Masri. But he said there was "general agreement" that some Palestinians would have to be involved in any talks.

Other U.S. officials acknowledged that the problem of finding potential Palestinian delegation members acceptable to all parties is likely to be discussed by Assistant Secretary of State Richard W. Murphy when he goes to the Middle East in mid-April to explore the various options.

Masri, following the lead taken by Egyptian President Hosni Mubarak when he visited here last week, stressed that any Palestinians chosen would have to be approved by the PLO. As a result, he said, their reception by U.S. officials would be regarded as American recognition of the PLO.

The idea of the meeting was among several proposals that Masri and Shultz discussed at their first meeting Wednesday and that might be explored further by Murphy when he visits the region. U.S. officials said that other topics included a Jordanian request for the United States to endorse a limited form of Palestinian self-determination and an Egyptian suggestion that the foreign ministers of the United States, Egypt and Jordan meet to help select members of the joint delegation.

The officials said that any U.S. declaration on self-determination would have to be made within the context of Reagan's September 1982 peace initiative calling for the Palestinian-inhabited West Bank and Gaza Strip to get independence "in association with Jordan" rather than as an independent Palestinian state.